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>it_dft</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN1021"
></A
><H2
>Name</H2
>it_dft&nbsp;--&nbsp;discrete Fourier transform</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN1024"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><P
></P
><A
NAME="AEN1025"
></A
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include &lt;it/fourier.h&gt;
      </PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>cvec it_dft</CODE
>( cvec v
        );</CODE
></P
><P
></P
></DIV
></DIV
><H2
>DESCRIPTION</H2
><P
> This function computes the discrete Fourier transform of the complex vector <CODE
CLASS="PARAMETER"
>v</CODE
>. The first element of the returned vector corresponds to the lowest frequency (DC value). For a complex vector <CODE
CLASS="PARAMETER"
>v</CODE
> that is actually a real vector (i.e. when all elements of <CODE
CLASS="PARAMETER"
>v</CODE
> have a null imaginary part), the output vector will be conjugate symmetric, that is V[N-i] = V[i]*, where V is the output vector of length N equal to the length of the input vector <CODE
CLASS="PARAMETER"
>v</CODE
>.  </P
><H2
>RETURN VALUE</H2
><P
>    The vector of discrete Fourier coefficients
   </P
><H2
>EXAMPLE</H2
><PRE
CLASS="PROGRAMLISTING"
>&#13;#include &lt;fourier.h&gt;

...

cvec v = cvec_new_string("1.0 4.0 1.0 -2.0");
/* analyse the vector using the discrete Fourier transform */
cvec vt = it_dft(v);</PRE
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